Design Trajectories: Four Experiments in PLE Implementation
M. van Harmelen1
Independent Consultant and University of Manchester, UK
(Received 31 August 2007; revised 17 September 2007; accepted xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx)
Increasingly, there is a shared understanding that the educational approach driving the development of
Personal Learning Environments (PLEs) is one of learner empowerment and facilitation of the efforts of selfdirected learners. This approach fits well with concepts of social constructivism, constructionism, and the
development and execution of learning plans. This paper how these have been increasingly supported in four
successive PLE prototypes. These prototypes have successively moved towards support for communities of
learners by basing PLE design on social networking services, and support for the formulation of learning
plans and transformation of those plans into public exhibits of growing knowledge.
Keywords: Personal Learning Environments; Social constructivism; Constructionism;
Learning plans; Social network service
Introduction
Increasingly, there is a shared understanding that the educational approach driving the development of
Personal Learning Environments (PLEs) is one of learner empowerment and facilitation of the efforts of selfdirected learners, also called autonomous or independent learners. This paper discusses four successive PLE
prototypes developed in the University of Manchester’s School of Computer Science, and shows how the
PLEs have increasingly provided support for the activities of self-directed learners.
As discussed here PLEs are part of a learning ecosystem:
 A learning ecosystem consists of resources available to a learner including other people (e.g. peer
learners, teachers), printed materials, computational materials (e.g. computer systems, including the
Internet), other resources (e.g.. physical models, paper, pens, …).

1
A personal learning environment comprises the computer-based parts of the learning ecosystem. We
may define computer-based parts to include desktop programs, browsers and other client programs,
servers and web services, ubiquitous and pervasive systems, and wireless and mobile telephony
devices. A PLE may be composed of one or more of these parts. If there is more than one component,
the components may be tightly coupled to other components, or may be loosely coupled, as for
Email: [email protected]
example in a “small pieces loosely bound” (Weinberger, 2002) 2 Web 2.0 approach, or may be in some
arrangement that contains both tightly and loosely coupled components.
In a self-directed approach learners take control of their own education, such that they may choose learning
outcomes to work towards, plan their learning to realise those outcomes, construct knowledge in the process
of learning, monitor progress towards outcome realisation, re-plan and modify outcome goals as need be, and
assess when they have realised their goals. This process may be performed alone or with the assistance of
others; be those others knowledgeable peers, mentors, or formally appointed teachers in a community that
constructs knowledge through a processes of social interaction (Vygotsky, 1978; Lave and Wenger, 1991).
While formally appointed teachers are of interest in formal educational systems, much of the author’s interest
is in the applications of PLEs in informal education, i.e. outside of the formal educational system.
Self-directed learning in communities is strongly reliant on social constructivist and constructionist
approaches to learning:
Social constructivism has as a central precept that knowledge is created by learners in the context of, and as a
result of social interaction. Social constructivist approaches are particularly aided by using social networking
service based PLEs as mediating mechanisms between learners, and particularly between geographically
distributed learners who might also use the PLE at different times. In learning communities teachers might be
learner peers, or in Communities of Practice, might be community members who have the current focus of
learning leadership, or might be formally appointed teachers assisting a class of learners. In a social
constructivist context, it is important for teachers to support scaffolding in a Zone of Proximal Development,
to help reduce the “distance” between the actual level of the learners’ development and the level of their
potential development (Vygotsky 1978).
In part this scaffolding can be supplied by learning plans, either constructed for the learning task in hand, or
found or provided; possibly altered or remixed as need be. The ability to reuse pre-prepared learning plans in
a PLE provides the answer to a critique of self-directed learning – that in encountering a new and complex
learning domain where a self-directed learner has no previous domain knowledge, the learner is incapable of
knowing what to learn. Thus, for example, the ability to reuse and remix learning plans is an important part of
the Open University’s approach to open content (Buckingham Shum 2006; Open University 2007).
If a social constructivist approach is to be adopted, then it is also important to consider how the growth of a
community of learners can be facilitated. Haythornthwaite (2005) discuses how latent ties, the ties that are
provided by membership of a social networking service, can be transformed into weak ties by public
communication, and how weak ties can be transformed into strong ties by private communication. Thus,
provision of suitable public and private communications channels should accompany other PLE facilities.
Constructionism (in Papert’s sense of the term) is particularly amenable to PLE approaches that enable the
construction of artefacts for public consumption: ‘Constructionism … shares constructivism's connotation of
learning as "building knowledge structures" irrespective of the circumstances of the learning. It then adds the
idea that this happens especially felicitously in a context where the learner is consciously engaged in
constructing a public entity, whether it's a sand castle on the beach or a theory of the universe.’ (Papert 1991)
Thus, in a constructionist approach to learning environments, it is important for learners to be able to use
Weinberger’s book predates much of Web 2.0, but the aphorism “small pieces loosely joined” has been
adopted by the Web 2.0 movement as one of its central precepts.
2
PLEs to construct and display public entities, for example, via constructs such as video presentations, blog
entries (for individual work) and wiki pages (for individual and group work). A PLE-based community of colearners may provide the audience for the public entity.
Experimental prototypes and trajectories of development
Four experiments with PLEs are described in the remainder of this paper:
 The Manchester PLE/VLE framework, an early (late 2004 – early 2005) experiment that produced a
framework that could be instantiated as a VLE or a PLE: In this scheme the PLE is a desktop or laptop
based client that is capable of both networked and stand-alone use.

An entirely browser and web server based PLE that used a “small pieces loosely joined” approach to
PLEs (in use mid 2005 till now).

Strawberry, a throw-away experiment in the development of a social software based PLE combining
community, blog, wiki, and file-sharing facilities (implemented late 2006).

A current project, mPLE, that builds on experience gained with Strawberry, but that is structured
around personal and community learning activities, and within that around learning plans and
constructionist artefacts (implemented to a usable state in 2007, with ongoing work as this paper is
written).
As can be seen from the table 1, the development of ideas represented by these four systems has steadily
progressed from support for isolated learners to support for learners working in communities that benefit from
social constructivist and constructionist approaches to education.
PLE
Manchester
PLE/VLE
Framework:
No social bias
Browser & Web
2.0 services:
“Small pieces
loosely joined”
Activity to support
Choose learning
outcomes to work
towards
Plan learning use existing
learning plans monitor
learning progress replan
if need be
Build (teachers) and use
(learners) scaffolding in
the ZPD
Support communities of
learners
mPLE: Integrated
social software
system with
learning plans and
co-construction


Co-construct knowledge
including for
constructionist public
consumption
Reflect on learning
Automatic notification of
interesting learning
outcomes, learning
partners and boundary
objects
Latent to weak ties:
Synchronous public
communications
Latent to weak ties:
Asynchronous public
communications
Weak to strong ties:
Synchronous private
communications
Strawberry:
Integrated social
software system
with
co-construction
*
*




 **
 **
 ***
 **
 **
 **
()
()
fora
()
* = if recorded in wikis
** = if recorded in wikis and blogs
*** = via transformation of learning plans to constructionist artefacts
( ) = planned as of 10/2007
Table1: The trajectory of design and the growth of support in successive PLE prototypes
The Manchester PLE/VLE Framework
The main goals of the Manchester PLE/VLE Framework were to:
 Provide a PLE that students could use while disconnected from the Internet. Potential applications
included use away from the University, including during travel, on field trips, and in other settings
where Internet connectivity is impossible to obtain, e.g. in teaching hospital wards where inter-patient
mobility is important, but where wireless connectivity is disallowed.

To supply a PLE suitable for life-long learning where, for the convenience of learners, a single PLE
would allow the learners the ability to engage with learning material drawn from different institutions.
Learners would generally be engaging with central VLE facilities while online, and with a subset of these
facilities replicated in a PLE on a personal machine while offline. Learners could choose to download learning
resources from the VLE to their own PLEs, work on these while disconnected, and then upload them to the
central VLE when the work was finished.
This led to an architectural choice of a replicated web server, Tomcat, as the central core of both the PLE and
the VLE. We had extensive experience in running a service using the Bodington VLE, and modifying it for
our own purposes. Because of ongoing experience of problems in updating Bodington’s relational database
table structure in response to inevitable changes in VLE functionality, we adopted a radically different storage
structure for the Framework, providing a Virtual File System (VFS) that included native indexing and search
of XML documents via an embedded XML database, and provided a sophisticated permissioning system
suitable for large-scale e-learning systems. Together Tomcat and the VFS provided a framework that could be
instantiated as either a VLE or a PLE, with custom webapps running on Tomcat supplying learning system
functionality for either kind of system.
Observations
The notion of running a complete web server on a personal machine is comparable to other heavyweight
client-based PLE approaches, for example running Eclipse as a PLE implementation platform on a personal
machine. The latter is the choice adopted for PLEX (CETIS 2006). Given modern personal machines, both
approaches are computationally reasonable.
However, given the stance of wishing to enable empowering education in social constructivist and
constructionist styles questions arise as to the pedagogic suitability of the Manchester Framework PLE. In
balance, the VLE-influenced architecture directs the use of the PLE towards a centralised and teacherdominated view of education. While this may be of interest in some institutions, it ultimately led to the demise
of our interest in the PLE/VLE Framework and development of alternative approaches.
A lightweight browser-based PLE
In 2005 the author started experimenting with a browser as a lightweight PLE, in part in response to the
heavyweight centralist approach discussed above. This was largely an experiment in independent learning
about Web 2.0 and web-based communities. The results have been a demonstration that, for someone who can
use web-based resources, a browser-based approach is very well suited to social constructivist and
constructionist approaches.
This idea of using a browser and the World Wide Web as a PLE was not unique at that time, for example,
previously Blackall (2005) captured the zeitgeist thus: "Why do we need a PLE when we already have the
Internet? The Internet is my PLE, ePortfolio, VLE what ever. Thanks to blogger, bloglines, flickr, delicious,
wikispaces, ourmedia, creative commons, and what ever comes next in this new Internet age, I have a strong
online ID and very extensive and personalised learning environment." In a slight variation, Attwell, in an
engaging video (Attwell 2006) claims that his PLE extends beyond the confines of his browser to also include
his desktop applications. Earlier approaches which incorporate web facilities but have a centralised unifying
component are Wilson’s (2005) Future VLE, and Tosh’s (2005) proposed development of that theme using
Elgg as a central component.
The implementation premise for the browser based PLE was simple, to use Firefox’s bookmarks toolbar as a
means of accessing web-based learning resources by initially populating the toolbar with bookmarks of sites
forming a distributed web-based PLE, later organising these sites within folders, either by topic, by site type,
or by both in categories. In general the bookmarked sites employed break down into categories of information
sources, means of tracking information sources, and means of recording knowledge as it is constructed by the
PLE user, in wikis and blogs. Figure 1 shows some bookmark toolbar menu detail. This organisation is most
importantly done in a way that makes sense to the learner, and it can easily be changed as user conceptions of
organisation and usefulness change.
Figure 1: A browser-based PLE with a personal toolbar and sub-menus set up to meet individual need.
Observations
The advantages to this approach are that:
 It's surprisingly easy to build a PLE like this when compared to the client approach (above) and social
networking service approach (below). A FireFox-based PLE might be called a “half-hour PLE”,
because just a half-hour’s worth of effort produces a usable PLE.

The PLE is continuously evolvable to meet user needs.

The PLE is very much learner controlled and suited to self-directed learning.
However, there are problems in the approach:
 Multiple logins are required, one per site (although as an exception Google services are increasing
single sign-on). The use of Firefox’s password manager and cookie based persistent logins ameliorates
this. Future schemes involving Identity 2.0 approaches (Identity2.0) will help more, but in practice
cookie-based session maintenance on single-user computers means that the login problem is not much
of a problem for many users.

Some technical knowledge is required to employ bricolage (Turkle and Papert 1991; Brown 2002) and
link between bookmarked sites to make a more homogenous PLE than that simply offered by
bookmarking. However, this difficulty will ease with time as more and more sites enable linking and
customisation by normal users without technically-based bricolage skills.
In practice the advantages far outweigh the disadvantages for the relatively technically skilled who are
interested in the use of a “small pieces loosely joined” approach.
Social software approaches
While the browser-based loosely-joined approach is useful for web-sophisticated learners who are happy
using a multiplicity of different systems on the web, there are many application areas in which an integrated
system is of more use: For example, in class settings or in life-long learning settings with less technically
sophisticated users. In such situations, adopting a social software approach with integrated social networking
services hosted on remote servers and accessed by browsers allows for community formation around learning
goals, cf. community formation around social objects (Engeström, 2005), and for peer-assisted independent
learning. Additionally there is a significant deployment advantage in a server and browser based approach;
avoiding the need for client-based PLE installation and maintenance.
At the University of Manchester we strongly interested in leveraging this approach, and are part way through
a second iteration of social networking service based PLE prototypes. Following sections discuss these two
iterations.
A first social software prototype: Strawberry
The development of Strawberry was initially a re-implementation and extension of Elgg. Elgg is a social
networking service that has many PLE-like characteristics. Elgg provides users with the ability to nominate
friends, form communities, blog, tag widely, comment, and upload files. Unfortunately, Elgg’s user interface
suffers from navigational and search problems. As an experiment in PLE design and implementation, a class
of postgraduate students, with guidance from the author, designed and implemented an Elgg-like system;
Strawberry. In the design of this prototype we were particularly mindful of Powazek’s (2001) claim that users
trust social software systems with good navigation facilities, although preferring this author’s weaker claim
that users don’t like using systems with bad navigation facilities. Consequently the Strawberry approach was
to provide a user interface that incorporated a clearer layout, better location clues, and better search and
navigational aids than those supplied by Elgg.
The Strawberry system catered for individual users, and the creation of communities of users with common
interests. Each user and each community was provided with a profile page, a blog, a wiki, and a media area.
References in blog posts and wiki pages could be made freely across users’ and communities’ blog posts and
wiki pages using simple extensions to WikiText. The media areas area allow sharing of various kinds of data
via uploads, browsing and retrieval. Some screenshots of the system appear in figure 2.
Figure 2: Strawberry, a first social software based PLE implementation
Strawberry was implemented in Ruby-on-Rails, mySQL, HTML, CSS and Javascript. Built in a short time, its
main purposes were to instantiate and test a paper prototype, and to gain a feel for the advantages and
disadvantages of implementing in Ruby-on-Rails. Disadvantages were related to the short implementation
time available (approximately 70 person days): Notably, the delivered system did not implement WYSIWYG
wiki and blog editing, essential for general use, and the system was somewhat fragile. Because of the throw
away nature of the prototype, we have no plans to rectify these problems.
Observations
Certainly navigational interaction and knowledge as to where one was in the system was better in Strawberry
in than Elgg. The appearance of both blogging and wiki facilities in the system seemed a strong advantage,
since these support different kinds of knowledge building activities.
However, the major shortcomings to Strawberry were the lack of the ability to construct learning plans that
might be used to realise particular learning goals, or to use or remix pre-prepared learning plans. This
shortcoming was rectified in the next prototype, mPLE.
A second social software prototype: mPLE
The design and implementation of our second social software based PLE, mPLE, is in the latter stages of user
testing and improvement prior to field trials. mPLE is explicitly designed to allow individual learners and
groups of learners to formulate their own learning goals, to express plans to realise those goals, and to
incrementally transform plans into material that expresses the state of learners’ knowledge as learning
progresses.
Learning plans are expressed as directed graphs where the nodes express either goals or sub-goals in the
learning plan, or material relating to goals and sub-goals. Plans can be changed and mutated as learning
progresses. Pre-prepared plans for particular objectives can be used and/or repurposed easily. Web-based
learning materials and external references can be easily incorporated into learning plans, particularly if they
are bookmarked in del.icio.us; see Figure 3, which shows one of a user’s del.icio.us links being dropped onto
a learning plan to provide supplemental material.
Importantly, during the process of learning users incrementally transform the goal nodes into documents and
diagrams that are artefacts that express the learners’ growing knowledge. In this way the plan itself is
incrementally transformed into a statement of a learner’s or learners’ developing knowledge, thereby
providing the public entity referred to by Papert. Learning plans, documents, and (soon) diagrams are
collaboratively editable by more than one user at the same time.
A social software ‘substrate’ supplies what have become the expected social software facilities; user profiles
and communities, where communities group users with similar (learning) interests. Future iterations of the
system will include other common and/or useful features of social software, including RSS feeds, Facebookstyle feeds, blogging facilities, and the ability to import foreign blog posts into the PLE. Because community
formation is important in peer-assisted learning there are plans for the integration of synchronous private
communications facilities into the PLE, by integrating Skype call buttons into the system. Public
communications facilities are also planned.
For reasons of easy scalability the server side is implemented in mySQL and PHP together with a particularly
database-access efficient PHP MVC framework (Hoyé et al 2006). Performance is further being enhanced by
the use of Xcache and memcache. With the combination of these facilities, existing measurements (Raffin
2007) indicate that the server-side facilities will be able to support one million registered users on a relatively
modest hardware configuration.
Figure 3: A user profile and construction of a learning plan in mPLE
The client side is currently implemented in Adobe Flex that is compiled to Flash to provide a Rich Internet
Application that is compatible across browsers. However, experience with implementation in Flex and with
user testing of the social software substrate leads us to want to re-implement the client side interface in
HTML, CSS, and Javascript, together with limited use of Flash for the implementation of the graph (i.e.
learning plan and public entity) editor. Some use is made of third party web services; del.icio.us for
bookmaking and Zoho for document editing facilities.
Observations
The success of an approach incorporating choice of learning goals and planning for goal realisation is still to
be proven, but initial reaction from learners and teachers in higher education is strongly positive. Practical
trails remain to be undertaken for the planning and knowledge artefact component of the PLE; these are
scheduled to occur in the 07/08 academic year.
We have chosen one million registered users as a target because there are considerable advantages to be
gained from operating on a large scale in finding learning partners and communities with common interests
including long tail (Anderson 2006) minority interests. An example of the latter might be supporting the entire
life-long learning community in a small country (the figure of a million registered users is the life-long learner
community size in New Zealand). While, as mentioned, supporting this number of registered users is
relatively easy on the server side, there are user interface and system functionality considerations of note. We
anticipate making a considerable effort to support a large number of users, for example in supplying facilities
to automatically find potential learning partners based on deduced interests, cf. BuddyFinder-CORDER (Zhu
et al 2007), and automatically notifying learners about potentially interesting boundary objects (Bowker and
Star, 1999).
Conclusions
The PLE field is still in development, and requires experiment with a variety of pedagogic approaches and
their support. It is a reasonable claim that different pedagogic approaches will tend to be supported by PLEs
implemented in different architectural styles and with different interactive functionality. Four PLE
implementations in three very different architectural styles have been described. These styles find different
places on the dimensions that describe a space of PLEs (van Harmelen 2006), and provide for two different
pedagogic approaches:
 Centralist teacher-led, supported by the Manchester Framework

Teacher-led and self-directed, supported by the browser and loosely-joined web service based PLE,
Strawberry, and mPLE.
While for technically skilled users a browser-based loosely-joined pieces approach works well, the approach
presents some difficulties for learners who are less than comfortable with multiple systems. Consequently,
this author’s preference is to move towards browser-based interfaces to PLEs implemented on top of social
networking services because the approach supports social constructivist and constructionist learning for those
who are not satisfied by a loosely-joined approach.
In concluding, it is worth considering metacognitive skills; the ability to formulate and direct one’s own
learning. Metacognitive skills involve all the self-directed learner activities mentioned in the introduction to
this paper, and are also crucially dependent on the ability to perform reflection. While reflection is widely
discussed as a desirable skill for learning, it remains hard to teach, and there is as yet no e-learning system
(that the author is aware of) that supports and enables the growth of reflective skills. Thus there remains an
important research question, with considerable practical implications for PLEs: Can we build PLEs that truly
enable the growth of reflective skills and other metacognitive skills, and thus enable the growth of selfdirected learners? Until this ability is realised PLEs will not achieve their full potential as an enabling
technology. However, support of activities to formulate learning goals and plan for their realisation as
provided by mPLE is an important step towards this larger aim.
Acknowledgements
The author acknowledges help by and input from a variety of people: The Manchester Framework is based on
an idea by John Maber. The design and implementation team included Stuart Anderson, Peter Crowther, Chris
Page, and Wykeen Seet. Strawberry was designed and implemented under the author’s supervision by
CS60172 students in the 06/07 academic year at the University of Manchester’s School of Computer Science.
The mPLE was designed and implemented to date with the help of Ian Bell, Gregory Bouteiller, Mathieu
Perin, Eric Raffin, and Ashish Ugade. The author’s ideas and thinking on PLEs have benefited from many
discussions in the e-learning community in the UK and beyond. Help from all these people is gratefully
acknowledged.
Notes on Contributors
Mark van Harmelen is an independent ICT consultant working largely in the e-learning space. He is also an
Honorary Research Fellow in the School of Computer Science, University of Manchester, U.K.
References
Anderson, C. (2006). The Long Tail: How Endless Choice is Creating Unlimited Demand. Random House.
Attwell, G. (2006). Personal Learning Environments. Video. Retrieved September 10, 2007 from
http://video.google.com/videoplay?docid=4152559760003745761
CETIS. (2006). The Personal Learning Environments Reference Model Project. JISC CETIS Wiki. Retrieved
September 10, 2007 from http://wiki.cetis.ac.uk/Ple
Bowker, G. C., and Star, S. L. (1999). Sorting Things Out: Classification and its Consequences. Cambridge,
MA: MIT Press.
Blackall, L. (2005). Die LMS die! You too PLE! Retrieved June 1, 2007 from
http://teachandlearnonline.blogspot.com/2005/11/die-lms-die-you-too-ple.html
Brown, J.S. (2002). GROWING UP DIGITAL How the Web Changes Work, Education, and the Ways People
Learn. USDLA Journal, Vol. 16, No. 2.
Buckingham Shum, S. (2006). Sensemaking on the Pragmatic Web: A Hypermedia Discourse Perspective.
KMi Techreport, KMI-06-16, Milton Keynes, U.K.: Open University.
Engeström, J. (2005). Why some social network services work and others don't — Or: the case for objectcentered sociality. Retrieved September 1, 2007 from
http://www.zengestrom.com/blog/2005/04/why_some_social.html
Haythornthwaite, C. (2005). Social networks and Internet connectivity effects. Information, Communication
and Society, VOl.8, No.2.
Hoyé, B., Manson, B., Perrin, M., and Raffin, E. (2006). Oolime. Retrieved June 1, 2006 from
http://www.oolime.com
Identity2.0 (2007). Identity 2.0. Retrieved July 1, 2007 from http://identity20.com
Lave, J., and Wenger, E. (1991). Situated Learning: Legitimate Peripheral Participation. Cambridge, U.K.:
Cambridge University Press.
Open University. (2007). Knowledge Mapping Quickstart Guide. OpenLearn LabSpace. Retrieved October
12, 2007 from http://labspace.open.ac.uk/course/view.php?id=2923
Papert, S. (2001) Situating constructionism. In Harel, I. and Papert, S. (Eds.), Constructionism, Westport,
Connecticut: Ablex Publishing Corporation.
Powazek, D. M. (2001). Design for Community: The Art of Connecting Real People in Virtual Places.
Indianapolis, IN: New Riders.
Raffin, E. (2007). Personal Learning Environments. MSc Thesis, University of Manchester.
Tosh, D. (2005). A concept diagram for the Personal Learning Landscape. Retrieved June 1, 2007 from
http://elgg.net/dtosh/weblog/398.html
Turkle, S., and Papert, S. (1991) Epistemological Pluralism and the Revaluation of the Concrete. In Harel, I.,
and Papert, S. (Eds.), Constructionism. Ablex Publishing Corporation.
van Harmelen, M. (2006). Personal Learning Environments. Sixth IEEE International Conference on
Advanced Learning Technologies (ICALT'06).
Vygotsky, L.S. (1978). Mind and society: The development of higher mental processes. Cambridge, MA:
Harvard University Press.
Wilson, S. (2005). Future VLE - The Visual Version. Retrieved June 1, 2007 from
http://www.cetis.ac.uk/members/scott/blogview?entry=20050125170206
Weinberger, D. (2002). Small Pieces Loosely Joined. Perseus Books Group.
Zhu, J., L. Gonçalves, A., Uren, V., Motta, E., Pacheco, R., Eisenstadt, M., Song, D. (2007) Relation
Discovery from Web Data for Competency Management. Web Intelligence and Agent Systems: An
International Journal, Vol.5, 4, IOS Press.